execute if score @s rmr.item.banner_with_rotten_smell.use matches 1.. if items entity @s weapon.mainhand carrot_on_a_stick[custom_data={id:"rmr:banner_with_rotten_smell"}] run function rmr:item/banner_with_rotten_smell/use
scoreboard players set @s rmr.item.banner_with_rotten_smell.use 0